Country widely recognised as stunner and very, very old (6)
I believe the answer is:
kosovo
'country' is the definition.
(I know that Kosovo is a country)
'stunner and very very old' is the wordplay.
'stunner' becomes 'ko' (a knock-out blow or KO stuns a boxer).
'and' is a charade indicator (letters next to each other).
'very' becomes 'so' (both can mean 'extremely').
'very' becomes 'v' (common abbreviation).
'old' becomes 'o' (abbreviation).
'ko'+'so'+'v'+'o'='KOSOVO'
'widely recognised as' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for kosovo that I've seen before include "Part of former Yugoslavia" , "Balkans area" , "Balkan region declared independent in 2008" , "UN-administered area of former Yugoslavia" , "Former province of Serbia that declared independence in 2008, capital Pristina" .)